1. Field of the Invention
The present invention relates generally to vehicles with internal combustion engines, and in particular to an exhaust system therefor with improved pipe end configurations.
2. Description of the Prior Art
Exhaust systems for internal combustion engines convey hot exhaust gases and the byproducts of combustion from the engine to the ambient atmosphere via various suitable emissions control devices such as mufflers, resonators, catalytic converters and the like. Exhaust systems are subjected to thermal stresses associated with the handling of hot exhaust gases and vibration stresses from vibration sources such as the engine and the operation of the vehicle over the road. Due at least partly to being subjected to such stresses, exhaust systems tend to require periodic repair and replacement of the entire systems and individual components thereof. Exhaust system repair and component replacement are factors in vehicle operating costs.
Vehicle and vehicle parts warranties often require repair or replacement of unserviceable systems, including exhaust systems, which fail within predetermined warranty periods. Exhaust systems and their components can cause significant warranty expenses to be incurred. Thus, an improved exhaust system with components having longer service lives could reduce warranty claim expenses and vehicle operating costs. Engines equipped with certain performance and/or efficiency enhancing features, such as turbochargers and the like, often require more frequent exhaust system components replacement due to higher exhaust gas temperatures than conventional internal combustion engines.
An important consideration in the design of exhaust system components is, therefore, to maximize longevity in service in order to minimize frequency of replacement. Various exhaust system designs have previously been proposed in an attempt to satisfy one or more of these criteria. For example, exhaust systems have been produced with rigid pipes, spiral-wound flexible hose, bellows-type flexible hose and with a variety of materials chosen for their characteristics of strength, resiliency, elasticity, thermal performance and resistance to the corrosive effects of exhaust gases and the environment. Typically, connections must be made between rigid pipes, including exhaust manifolds, muffler pipes, tail pipes, etc., and flexible components such as flexible hose installed for its ability to accommodate vibration and relative movement between the more rigid components. The connections between such different components are often a source of wear and component failure due to differential movement between the connected components.
Exhaust system connections can be accomplished in various ways, including weldments, clamps, etc. Materials such as stainless steel, aluminum, galvanized metal and various alloys have been used to fabricate the exhaust system components in order to reduce the effects of corrosion and rust. However, a problem typically encountered in installing a muffler system relates to pipe edges, which are often square-cut by pipe cutting equipment and which tend to cut and wear other components as they move relative to each other. The potentially damaging effects of such sawed-off pipe ends are typically made worse by vibration and thermal stress associated with operating conditions. Areas contacted by exhaust pipe ends are therefore often the first areas to fail and require component replacement.
Heretofore there has not been available an exhaust system with improved pipe end configurations having the advantages and features of the present invention.
In the practice of the present invention, a vehicle is provided with an internal combustion engine having an optional turbocharger. An exhaust system includes an exhaust pipe connected to the engine and an emissions pipe which is connected to emission control component, such as a catalytic converter, muffler or resonator. A flexible hose coupling connects the exhaust and emission pipes. The exhaust and emission pipes have ends which are constricted or tapered to form annular clearances with a slightly larger bore of the flexible hose coupling. The exhaust and emission pipes can be connected to the flexible hose coupling in any suitable manner, such as by clamps, weldments and the like. A liner sleeve can be telescopically received in the flexible hose coupling and can in turn telescopically receive the exhaust pipe end for lining a portion of the flexible hose coupling bore.
The principle objects and advantages of the invention include: providing a vehicle with an improved exhaust system; providing such an exhaust system with improved pipe end configurations; providing such an exhaust system with pipe end configurations which reduce exhaust system component wear; providing such an exhaust system with pipe end configurations which are tapered to form annular clearances with other exhaust system components; providing such an exhaust system which can reduce the frequency of exhaust system and exhaust component repairs and replacements; providing such exhaust system which can reduce vehicle operating costs; providing such an exhaust system which is adaptable for use with vehicle exhaust systems comprising various types of metal; providing such an exhaust system which is adapted for use with vehicles having turbo charged engines; and providing such an exhaust system which is efficient in operation, capable of a long operating life, economical to manufacture and particularly well adapted for the proposed usage thereof.
Other objects and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention.
The drawings constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof.